The present invention relates to a controller for an internal combustion engine and a method for controlling an internal combustion engine.
For example, Japanese Laid-Open Patent Publication No. 2016-169665 describes a controller that executes dither control in which when a temperature increase request is made to increase the temperature of an exhaust gas purification catalyst (exhaust gas purification device), some cylinders are selected to be a rich combustion cylinder, the air-fuel ratio of which is richer than a stoichiometric air-fuel ratio, and the remaining cylinders are selected to be a lean combustion cylinder, the air-fuel ratio of which is leaner than the stoichiometric air-fuel ratio.
Japanese Laid-Open Patent Publication No. 2013-234673 describes a controller that performs a multi-injection process (divided injection process) in which fuel is supplied to each cylinder through multiple injections in one combustion cycle.